Paul-flechet



I nometer; Fig. 2, a vertical and longitudinal UNITED STATES PATENTOrricn.,

'PAUnFLcHEr or Panis, FRANCE IMPROVEMENT-HN sun-mms.. u

Speciiication forming part of Letters Patent N o. 35,225, .dated May 13,i862.

' a plane passes, the trace of which is shown by m n in Fig. 4 and by ZZin the projection, Fig. l, of the spherical section. The beginning ofthe Vernier is in this plane, as well as two notches, and u., Figs. land 3, which receive -To aZZ whom zit may concern: f

Be it known that I, PAUL FLCHET, of Paris, in the Empire of France, haveinvented certain new and useful Improvements iii Solar Time-Keepers orChro ometers; and I do hereby declare the nature of the said'inventionand in what manner the same is to be performed to be particularlydescribedv and ascertained in and by the following statement thereof,reference being had to the drawings ,hereunto afinexed-that is to say:This solar chronometer may be used generally and in all quarters of thegl0be. It gives the vhour in true and mean time without the aid of anytable of corrections. e lt also indicates -the meridian as well as thelatitude of the spotwhere it is used, and itis self- Y verifyii-ig.l Itisv illustrated by the accompanying drawings, in which Figure lrpresentsfa longitudinal elevation of my'im'provedapparatus or solarchro- Its trace` k It on the projection of the spherical section /Z Z,Fig. 5, will be the equinoctial line. The two lines ZZ and kk beingobtained, I draw the curve Z Zi Z k is traced, showing the equation oftime for each day of the year according to LAnnuaire du Bureaudes'Longitudes, and for the focal `distance i Z from the lens. Thefline' Z Z represents true time.

maintainedin a Yhorizontal position; second, that ,the piece B may' turnvertically about the axis f and be secured to the piece A bya section;Fig. 3, a front view of the upper dial. pressure-screw; third, that the'piece kC may Fig. 4' shows the Vernier or sliding scale with itsbracket, and Fig. 5 a plan View of the whole appara/tus. Itis composedof four principal parts, A, B, C, and D.

A, Figs. l andl 2, represents astand having'y i a hole in i forattaching and adjusting the about the axis h and may bya screw be fixedto the piece B; fourth, that the pieces D D',

independent of one another, and they can be combined or not by thescrews and 'tighteningbolts. It is indispensable, iii-st, that the axisf of the piece B bein a plane perpendicular `toY the vertical face ofthe disk c., projecting piece in the support A; and, second, that theaxis 71.- h of the piece C be parallel with the `suitable bed-plate.

e is a projecting piece with 'vertical front, against which the part Bis iitted and secured by an axis, f, about which it is 'free to move, ascrew keeping itixed, when desired.`

gis a socket in the part B, into which: thel axis h of the spherical capC takes. The upper circumference of this cap C is divided ntotwenty-four equal parts, indicating -the two periods of from noon tomidnight and `from midnight to noon, as shown at'.Fig. 5.

a second plane is dra. n perpendicular to hv The partsare constructed insuch. manner,

turnin a planeperpendicularto that of B` Each division, whichrepresents'anv hour, is The operation of the instrument is asfolysi'ibdivided for the quarters and minutes. The lows: Supposiiig itto be resting on the hoi-i'- .plane passing through the lineof axis, h.h and zontal support A, turn the piece C to bring lthe wholecorresponding to neen, is parallel the zero of the Vernier. to noon,stretch the .with the vertical face. Thepieees .D D are thread t u, andsuspend from it the plu1nbfixed to the spherical cap-.byl'sei'ews That'line-:c fg. The linetu is common to the two marked D carries a'lens,z', and g-.ffthatinaiked `planes h h' z' Z Z and tu a; y, whichisrendered D is a sect'on of a' sphere,Z Z, of which the vert-ical b ymaking the two planes to coincide,

Alens z' is the center. Y and that in different positions, so as to becer.-l

` o' is a Vernier on the capfC. ',lhron-gh the;4 vtain that the plane isvertical. That deter- ,axis hhand the point 'L'.(theceiiter of thelens)miiAed, -the piece A' is definitely iix'ed in that vis being` performed.

position and the plumb-line is removed. ln order to give the piece l thedesired inclination at mid-day, place the .zveroof the Vernier at noonand bring the focus of the lens on the point of the curve c()rrespondingto the day on which the operation takes place,tighten' the axis, theinclination of which piece must l' not again be Varied for thepartienla/rlatitude.

'l`he apparatus may be oriented or set to mark the bearing or situationwith respect to the four cardinal points at anyhour;l but it is-at sixoeloek in themorl'iing Aor evening that the operaiion .atl'ords ihegreatest exaetness. Without displacing the axisj', ,bring the focus oi'the lens i upon the point of the curve eorresponding,l to theday onwhich the i.)peratio'n The a1 )pa1atlis w'ill be in position and theVernier will giVe the hour.

llowever, as theie are two positions possible,

it isnecessary to choose that in which the Vernier is to the right 'ofnoon, it' the operation takes place in the evening', and that where theVernier is to the left or' noon, it' the operation takes place in themorning. The piece (l alone remains movable, and the Vernier will givethe hour mean time when the focus falls on the curVe, and it willgivethe 'true time when the focus falls on the straight line.

' Therthe instrument is at work, the three 'pieces are: one horizontal,corresponding with the bearing in respect to the cardinal pon ts; onevertical, corresponding with the latitude;

the third equinoctial, corresponding with the hour. One ot thesequantities beingI known, the instrument gives the other two by the sun.If a compass is used to .ascertain thebearing with respect t0 thelcardinal points, the instrument will giVe the latitude and the hour. `Bycomparing' the hour of the place with that ot the iirst meridian giVcnby a chronometer, the longitude can be ascertained, and consequently thegeographical position of the place where t-hc operation takes place. Forpurposes of, instruction the piece carrying; the Vernier can be replacedby a terrestrial globe, and placed in such manner that all its circleswould be parallel with analogous circles on the earth, so that when thesun shines all the lighted parts on'the earth'will haVeth ei r analogousparts li ghted on the globe. lt is Very interesting to watch on this'terrestrial globe the sun rising and setting'.

'lhe instrument may be made ot' inoxidizable metal and enameled, andparts of itsueh as the cap (l-may be of glass or other mate ri al.

And having; new deseribed'the nature of my said inVention and' in whatimanner the sameis to be performed, l deel -e that I do not limitmyselt' to the particular arrangement and materials -hereinbeforedescribed, for the

